Inorganic-conducting polymer particles were prepared to enhance physical and chemical properties by forming hybrid nanocomposites, which would improve the electrorheological (ER) effect of their suspensions. Polypyrrole (PPy)-SnO2-methylcellulose nanocomposite particles were synthesized by controlling the ratio of pyrrole, SnO2, and methylcellulose during the polymerization. The ER and dielectric properties of the PPy-SnO2-methylcellulose nanocomposite suspensions were investigated. The ER response increases with the increase in the SnO2/Pyrrole ratio and also depends on the amount of methylcellulose amount during the polymerization, showing a maximum ER behavior.